arXiv Machine Learning By Yoann Poupart, Aur\'elie Beynier, Nicolas Maudet

Policy Gradient Steering: Interventions from Behavioral Objectives

Read the original on arXiv Machine Learning →

arXiv:2607. 27574v1 Announce Type: new Abstract: Activation steering has emerged in large language models as a lightweight alternative for dynamically changing a model's behavior at inference time.

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arXiv Machine Learning
Sep 11

UBCL: A Reinforcement Learning Framework for Controllable and Diverse Player Behaviors

The paper presents UBCL, a reinforcement learning framework that generates controllable and diverse player behaviors without using human gameplay data. By defining behavior in an N‑dimensional continuous space and training a single PPO‑based multi‑agent policy with target behavior vectors, the method learns how actions affect behavioral statistics such as aggressiveness, mobility, and cooperativeness. Experiments in a custom Unity multiplayer game demonstrate that UBCL achieves greater behavioral diversity than a win‑only baseline and accurately matches specified behavior vectors across a range of targets.

By Atahan Cilan, Atay \"Ozg\"ovde
arXiv AI
Sep 18

UnifiedPlayers: Enhance Tool-Integrated Reasoning in Agentic Reinforcement Learning

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By Wenjie Liao, Liangjie Zhao, Zehong Cao
arXiv Computation and Language
Sep 21

ArenaFlow: From Trajectory Ranking to Hierarchical Credit Propagation for Open-Ended Agent RL

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By Qiang Zhang, Ruixue Ding, Fanrui Zhang, Xi Chen, Boli Chen, Shihang Wang, Yinfeng Huang, Yi Zheng, Pengjun Xie, Kaipeng Zhang, Jiawei Liu, Zheng-Jun Zha
arXiv AI
Sep 23

Synthesizing Reactive Character Behaviors for Continuous Games via Programmatic Policy Search

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By Maxim Gumin, Hsueh-Ti Derek Liu, Victor Zordan, Daniel Ritchie